Introduce a New Model for Expansion Behavior of Thick-Walled Cylinder under Internal Explosive Loading with Numerical Analysis

Evaluation of thick-walled cylinders behavior under high strain rate loading is of great importance because of their many applications. Most of the studies around these structures were performed in the state of static and quasi-static. Therefore، development of analytical model in structures loaded with high rates in dynamic state and in complete plastic domain is valuable. The main purpose of this article is to derive a mathematical model based on plasticity flow rules in order to assess the expansion behavior of isotropic thick-walled aluminum cylinder containing TNT. Through this، the equations of radial and circumferential stresses derived from equation of equilibrium and then radial velocity could be calculated by iterative procedure applying instantaneous explosion product pressure as boundary conditions which is variable and depend on geometry of cylinder and also modification of dynamic strength at each moment with considering the strain rate. Therefore، strain rate with its effect on dynamic strength is of importance points in this article. After extraction of radial velocity، other process parameters will be determined and used as input data for the next stage. Furthermore، computer simulation was done، which shows good agreement with the analytical results.